This invention pertains to the repair of refractory structures by gunning. In particular, it pertains to a method wherein aluminosilicate aggregate, plastic clay, graphite, and sodium silicate binder are admixed, placed in a moisture sealed container which is stored for a period of time up to six months, the admixture then being retrieved from the container, placed in a gunning apparatus and projected through the gun nozzle onto a refractory structure, water being added at the nozzle of the gun.
Refractory compositions containing graphite are well-known, for example as disclosed in U.S. Pat. No. 3,010,837, the graphite being added to impede penetration of iron into the refractory, thus reducing the rate of corrosion and erosion of the refractory in contact with molten iron. It is also known to predampen gun mixes, for example as disclosed in U.S. Pat. No. 3,360,594, in order to reduce dusting and rebound when these compositions are gunned. However, such predampening has previously been done on the job site, immediately before application of the refractory. Finally, it is known to ship refractory mixes intended for use as ramming mixes or as plastic materials in a form with the water or other tempering liquid already included, for example as disclosed in U.S. Pat. Nos. 3,832,193 and 3,998,648.
The present invention is directed to the problem of producing a gun mix of reduced dusting and rebound, combined with enhanced adherence, cohesiveness, and strength by use of a liquid binder which is placed in the composition at the point of manufacture.